It is well known that examination for characteristic neoplastic cells in exfoliated tissue or cell specimens from, for example, the secretions, exudates, transudates, scrapings or brushings from various human organs or tissues may permit the diagnosis of malignancy. Exfoliative cytology has been found to be so valuable in the detection of early cancer of the uterus and uterine cervix that it is usually performed as a routine part of the annual examination for all adult women, see Pathologic Examination, Enfoliative Cytologic Study, Chapter 24, pages 362-365.
Exfoliated tissue or cell specimens may also be obtained from, for example, the trachea and bronchi, stomach, rectum and colon, urinary tract, serous sac fluids, cyst fluids, synovial fluids, glandular secretions and exudates. Methods for obtaining, collecting and, if necessary, preserving the specimens may vary according to the preference.
Each collected specimen is spread intact as an even layer over a clean microscope slide and submerged in, for example, an alcohol-ether fixative for about one hour. After being fixed, and without being allowed to dry, the layer is coated with glycerin and the whole sandwiched between two glass slides. The slides are then sent to a laboratory for staining and microscopic diagnosis by trained and experienced pathologists or cytologists.
While the microscopic diagnosis of exfoliated tissue or cell specimens is useful, the diagnostic interpretation:
i) has to be carried out by skilled personnel, PA1 ii) is not completely reliable due, for example, to abundant mucous, trichomonas infection or atrophy, and PA1 iii) cannot accurately detect, for example, malignancy in tissues or cells in the pre-malignant or early malignant stages. PA1 i) a simple test on the specimen, and the interpretation thereof, can be carried out by personnel having no medical skills and after a relatively brief course of training, PA1 ii) with proper care, interpretation of the test results is reliable, and PA1 iii) malignancy in tissues or cells can be detected in the pre-malignant or early malignant stages. PA1 a) directing a beam of infrared light at a specimen of exfoliated cells, and PA1 b) determining if an anomaly is present in the specimen by spectral analysis of the infrared absorption of the specimen, at at least one range of frequencies, to ascertain whether at least one change in the infrared absorption characteristics has occurred, due to vibration of at least one functional group of molecules, in the specimen, which is characteristic of that anomaly.
There is a need for a method of detecting the presence of anomalies in exfoliated cells wherein:
It has already been proposed in the applicants' co-pending Canadian Patent Application No. 2,008,831-1, filed Jan. 29, 1990, "Method of Detecting the Presence of Anomalies in Biological Tissues and Cells in Natural or Cultured Form by Infrared Spectroscopy", P. T. T. Wong and B. Rigas, which corresponds to U.S. Pat. No. 5,038,039, to detect the presence of anomalies in biological tissues and cells in natural and cultured form (e.g. cancerous tissues or cells) by infrared spectroscopy. A beam of infrared light is directed at a sample of tissue or cells in natural or cultured form containing the cells to be tested, and the anomaly is detected at at least one range of frequencies by determining whether changes in infrared absorption have occurred due to the vibration of at least one functional group of molecules present in the sample which is characteristic of the anomaly.
The method taught by P. T. T. Wong and B. Rigas is applied in the examples to biopsed tissue or cultured cells. In particular, P. T. T. Wong and B. Rigas, page 7, line 20 to page 8, line 36, teach the detection of colorectal cancer from colonic mucosa immediately following bovel resection, i.e. colonic mucous membrane immediately following surgical removal of a section or segment of the bowel.